Early
toolmakers were masters of the craft of flint knapping. They
knew that to strike off the right kind of flakes and blades, they
must carefully prepare the flint cores they were working with and
keep them in good condition.

First they had to create a flat, or nearly flat platform on the
top. This is called the striking platform. Next, when they struck away a flake it would leave a
slight curving lip below the edge of the platform. If this
lip became too big, it made it hard to see how far back they needed to
hit to get the next flake off successfully. So they would
prepare the edge of the core after every few blows by trimming it
back. (see diagram below).

This edge preparation work is done between striking off flakes by
gently tapping or rubbing the sharp, curving lip of the core
platform with
the hammer stone to trim it back.

The Mesolithic cores illustrated at the right show (top) a core
from which numerous flakes have been struck but where the
toolmaker didn't bother to do any further edge preparation.
The sharp, curving lips are clearly visible. It may be that
the toolmaker didn't bother because he or she chose to discard the
core as no longer useful.

Below is a similar Mesolithic core from the same period but
where the toolmaker has carefully prepared the edges for further
knapping, but has then apparently changed his or her mind and
discarded the core.

Blade cores and Flake coresArchaeologists refer to the shards of flint struck from a core
as flakes. Many are merely waste flakes and are sometimes
referred to by the French term debitage. A smaller number are
suitable for further work and are re-touched to become tools such
as scrapers.

A flake that is at least twice as long as it is wide is
referred to as a blade. Some are suitable for use as knives,
others for use as side scrapers or end scrapers.

A core from which blades are deliberately struck is known as a
blade core (see example illustrated at right). Some cores
are deliberately worked from both ends and are referred to as
bipolar cores, like the one illustrated here.

Multi-pole cores and rejuvenation flakesIn the Mesolithic, it became common for a good quality flint
core to be rotated and worked from many different angles, in order
to make the most of the material. Sometimes, when a core
became unworkable (perhaps due to mis-hits on the working
platform) the knapper would strike off a flake to create a new
platform. These core rejuvenation flakes were sometimes
discarded and sometimes retouched for use as a scraper, like the
one illustrated right.

Microliths and very small scrapers (sometimes called thumb
scrapers) are struck from correspondingly small cores.
Sometimes, when discarded, these can be just a few millimetres
across.

Getting started - crested bladesOne of the most difficult parts of striking flakes or blades
from a core is getting started in the first place. The flint
knapper would find a promising looking nodule of flint but usually
it would have a smooth outside with no obvious place to start
striking flakes off cleanly, so the knapper would start his or her
own. To do so, they would 'nibble' away the crest of a long
blade and then strike this off. This first piece is very
distinctive - triangular in section with many small facets nibbled
away along its length.